Probiotics Tested in Eye Fatigue from Screens

Guest BloggerMicrobiome Environment

Bleary-eyed coders and sleepy gamers are a common sight these days.

The digital age has been an eye opener: laptops, phones and tablets stress our visual senses to levels never seen in history. Eye fatigue, pain, blurred vision, dry eyes—all results of our love affair with screens.

While the act of staring continuously with reduced blink rates is one obvious and much studied cause of ocular fatigue there are further problems with blue light emitted from screens.

Retinal damage

Blue light can damage retinal cells, which has been reported to be related to eye fatigue.

And here’s the segue into the probiotic connection:

The retina performs beautifully with its ganglion cells, photoreceptor cells and also immune cells such as retinal macrophages. These cells are critical in fighting the inflammation caused by blue light.

To reduce oxidative stress, anti-oxidants, carotenoids, polyphenols, and n-3 long-chain fatty acids have been tested for improving eye health in mice and humans. Results are varied.

Now, researchers in Japan are asking whether probiotics– given their role in reducing inflammation—may also improve eye function under the duress of screen stress. The scientists recently evaluated the effects of a strain of Lactobacillus paracasei on ocular disorders and symptoms of eye fatigue among healthy human subjects. The study was published in Nutrients journal.

The study
  • 62 healthy Japanese volunteers of 35 to 45 years of age who had experienced eye fatigue were randomized into two groups and given a placebo or a strain of Lactobacillus paracasei as supplements for eight weeks.
  • The key endpoint which indicated eye fatigue was determined by something called “critical flicker frequency (CFF)” four and eight weeks after the start of supplementation. CFF is the frequency at which a flickering light is indistinguishable from a steady, non-flickering light.
  • Subjective reports were also recorded: ocular pain, blurred vision, excess tearing, stiffness of waist or shoulders, ocular fatigue sensation, dazzled vision, double vision, frustration, stuffy head, eye redness, and headache.

Both objective parameters and subjectively quantified eye fatigue symptoms were alleviated with daily ingestion of the probiotic.

The authors also reported results from “In vitro” testing (test tube or culture plate):

  • This Lactobacillus paracasei strain activated M2 macrophages and induced the anti-inflammatory cytokines
  • Retinal cell death was suppressed

Real harm may be done to your vision with use, overuse, of modern screen devices. Probiotics may be helpful in alleviating some of that damage.